A cellular phone having a sliding mechanism that is reduced in size is disclosed in JP-A-2006-333079. The sliding mechanism disclosed in JP-A-2006-333079 is configured that an actuator slides over a shaft. The sliding mechanism has a cylindrical spring is provided on the shaft and imparts resilient force to sliding action of the actuator. The shaft of the sliding mechanism is mounted to a frame of an upper case of the cellular phone, and the actuator of the sliding mechanism is attached to a lower case, whereby the upper case and the lower case slide with each other. The frame needs to have a space to allow the spring and the actuator to slide.
Another example of such sliding mechanism for a portable equipment is disclosed in JP-A-2006-245347. The sliding mechanism disclosed in JP-A-2006-245347 has a configuration similar to that disclosed in JP-A-2006-333079.
An example of a cellular phone having a sliding mechanism provided with a flexible substrate as a connection cable between upper and lower cases is disclosed in JP-A-2006-128808. In the sliding mechanism disclosed in JP-A-2006-128808, a bent portion of the flexible substrate moves within the case in conjunction with the sliding action.
An example of a cellular phone having a sliding mechanism provided with a lead wire as a connection cable between upper and lower cases is disclosed in JP-A-2005-167309. In the configuration disclosed in JP-A-2005-167309, the connection cable located between upper and lower cases is a wire having a sheath made of resin and 30 lead wires being bundled together. A coil spring is used for a spring for urging purpose that slides the upper and lower cases. The connection cable is disposed in a space within the coil spring and bents in accordance with expansion and contraction of the coil spring to be extended and shortened.
In the sliding mechanism disclosed in JP-A-2006-333079, a slidable distance becomes essentially equal to the length of the shaft. Therefore, in order to acquire a desired slide distance, the length of the shaft needs to be increased, and a frame to which the shaft is to be attached also becomes longer. Hence, there is a problem of a structural limitation being imposed on the upper case on which the frame is mounted. The configuration disclosed in JP-A-2006-245347 also has a similar problem.
The flexible substrate disclosed in JP-A-2006-128808 is generally formed to be wide, and a bent portion of the substrate is movable in the case. Hence, the movable space needs to be ensured in the case, and there is a problem of difficulty being encountered in designing the case to be small in size. The flexible substrate needs to be movable by an amount corresponding to the slide distance of the case, and a certain degree of high rigidity is required. A lead wire having low rigidity, or the like, has a problem in allowing the lead wire to be extended and shortened in the case by bending the lead wire.
The configurations disclosed in JP-A-2006-128808 and in JP-A-2005-167306 have a problem of difficulty being encountered in smoothly inserting or withdrawing the connection cable in or from a narrow space in the coil spring that expands or contracts in accordance with the slide distance of the case without being stuck therein.